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<TITLE>TSP (audio) - GenNoise</TITLE>
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<H2>GenNoise</H2>
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<H4>Routine</H4>
<DL>
<DT>
GenNoise [options] AFile
</DL>
<H4>Purpose</H4>
<DL>
<DT>
Generate an audio file containing uncorrelated Gaussian noise samples
</DL>
<H4>Description</H4>
This program generates zero-mean uncorrelated pseudo-random Gaussian
deviates.  These white noise samples are written to an audio file.  Each
invocation of this program generates a different random sequence.  Options
are available to specify the number of samples, the sampling frequency and
the data format of the output file.
<H4>Options</H4>
<DL>
<DT>
Output file name: AFile:
<DD>
Specifying "-" as the output file indicates that output is to be written
to standard output.  If the output file type is not explicitly given (-F
option), the extension of the output file name is used to determine the
file type.
<PRE>
  ".au"   - AU audio file
  ".wav"  - WAVE file
  ".aif"  - AIFF sound file
  ".afc"  - AIFF-C sound file
  ".raw"  - Headerless file (native byte order)
  ".txt"  - Headerless file (text data)
</PRE>
<DT>
-d SDEV, --std_deviation=SDEV
<DD>
Standard deviation of the noise samples in normalized units, default
0.03. The standard deviation can be given as a real number (e.g.,
"0.03") or as a ratio (e.g., "983.04/32768").
<DT>
-x SEED, --seed=SEED
<DD>
Seed for the random number generator, default from current time.
<DT>
-n NSAMPLE, --number_samples=NSAMPLE
<DD>
Number of output samples to be generated.
<DT>
-s SFREQ, --srate=SFREQ
<DD>
Sampling frequency for the output audio file, default 8000.
<DT>
-F FTYPE, --file_type=FTYPE
<DD>
Output file type.  If this option is not specified, the file type is
determined by the output file name extension.
<PRE>
  "AU" or "au"             - AU audio file
  "WAVE" or "wave"         - WAVE file
  "WAVE-NOEX" or "wave-noex" - WAVE file (no extensible data)
  "AIFF-C" "aiff-c"        - AIFF-C sound file
  "AIFF" or "aiff"         - AIFF sound file
  "noheader" or "noheader_native" - Headerless file (native byte
                             order)
  "noheader_swap"          - Headerless file (byte swapped)
  "noheader_big-endian"    - Headerless file (big-endian byte
                             order)
  "noheader_little-endian" - Headerless file (little-endian byte
                             order)
</PRE>
<DT>
-D DFORMAT, --data_format=DFORMAT
<DD>
Data format for the output file, default integer16
<PRE>
  "mu-law8"   - 8-bit mu-law data
  "A-law8"    - 8-bit A-law data
  "unsigned8" - offset-binary 8-bit integer data
  "integer8"  - two's-complement 8-bit integer data
  "integer16" - two's-complement 16-bit integer data
  "integer24" - two's-complement 24-bit integer data
  "integer32" - two's-complement 32-bit integer data
  "float32"   - 32-bit floating-point data
  "float64"   - 64-bit floating-point data
  "text"      - text data
</PRE>
The data formats available depend on the output file type.
AU audio files:
<PRE>
  mu-law, A-law, 8/16/24/32-bit integer, 32/64-bit float
</PRE>
WAVE files:
<PRE>
  mu-law, A-law, offset-binary 8-bit integer, 16/24/32-bit integer,
  32/64-bit float
</PRE>
AIFF-C sound files:
<PRE>
  mu-law, A-law, 8/16/24/32-bit integer, 32/64-bit float
</PRE>
AIFF sound files:
<PRE>
  8/16/24/32-bit integer
</PRE>
Headerless files:
<PRE>
  all data formats
</PRE>
<DT>
-I INFO, --info=INFO
<DD>
Audio file information string for the output file.
<DT>
-h, --help
<DD>
Print a list of options and exit.
<DT>
-v, --version
<DD>
Print the version number and exit.
</DL>
<P>
By default, the output file contains a standard audio file information
string.
<PRE>
  Standard Audio File Information:
     date: 1994-01-25 19:19:39 UTC    date
     program: GenNoise                program name
</PRE>
This information can be changed with the header information string which is
specified as one of the command line options.  Structured information records
should adhere to the above format with a named field terminated by a colon,
followed by numeric data or text.  Comments can follow as unstructured
information.
<PRE>
  Record delimiter: Newline character or the two character escape
      sequence "\" + "n".
  Line delimiter: Within records, lines are delimiteded by a carriage
      control character, the two character escape sequence "\" + "r",
      or the two character sequence "\" + newline.
</PRE>
If the information string starts with a record delimiter, the header
information string is appended to the standard header information.  If not,
the user supplied header information string appears alone.
<H4>Author / version</H4>
P. Kabal / v5r0a  2003-11-06
<P>
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